Employment contracts: cross-sectional and longitudinal relations with quality of working life, health and well-being.

OBJECTIVES: The aim of this study was to enhance (i) insight in the relationship between different types of employment contract and the quality of working life, health and well-being, and (ii) our causal understanding of these relationships by comparing employees whose contract type changes across time.
METHODS: Analyses were based on a two-year prospective cohort study. Cross-sectional analyses were based upon a sample of 2,454 Dutch employees (2004). Longitudinal data were available for 1,865 respondents (2004-2006). We distinguished among 5 contract types, and subgroups of 'Upward' (i.e., towards permanent employment) and 'Downward' (towards temporary employment) movers across time. Data were analysed with analysis of variance and cross table analysis.
RESULTS: Cross-sectionally, we found differences between contract types in quality of working life: generally permanent employees had better jobs, whereas temporary agency workers and on call workers had more 'bad work characteristics'. We also found a difference in health behaviour (smoking) and that psychological health was worst among temporary agency workers. In longitudinal analyses we found some evidence that a positive change in employment contract was associated with a better quality of working life and better psychological health, whereas the opposite was true for a negative contract change.
CONCLUSIONS: The quality of working life, health and well-being are unequally distributed over employment contract groups. Temporary agency workers and on-call workers deserve special attention in terms of job design and human resource management.